Armrests are incorporated into vehicles for ergonomic reasons and comfort and convenience of both drivers and passengers. Armrests may be attached to or integrally formed as part of an interior door panel, a seat assembly, or a center console. Some armrests may be stationary, fixed, collapsed, extended, or rotated depending on the mounting location and the system that it is incorporated within.
A traditional armrest assembly consists of four main components, a main substrate, a foam backplate, an armrest casing, and a foam element. The main substrate provides support and structure to the armrest. The foam backplate is coupled to the main substrate and the combination thereof is inserted into an armrest casing. The foam element resides within a cavity formed by the coupling of the substrate, the backplate, and the casing. The foam element provides flexibility, energy absorption, and occupant comfort.
A common process utilized to manufacture and assemble a vehicle armrest, such as that contained within or on a door assembly, includes five main tasks. The process begins with the injection molding of the main substrate. A plastic material is injected into a mold, which is then cured to form the main substrate. The second task includes the “over molding” of the armrest casing, often formed of a vinyl material, over the main substrate. Following the over molding of the armrest casing, the foam backplate is attached or fastened to the substrate. The fourth task includes the injection of expandable foam through the backplate into the cavity between the substrate, the casing, and the backplate. The foam expands within the cavity and has a resulting exterior shape that is substantially similar or identical to the internal shape of the cavity. Finally, the foam is cured to form the finished armrest.
Although the foam element can provide the desired characteristics for an armrest, such as flexibility and energy absorption, the process used to form and cure the foam element is time consuming and costly. The amount of time required to inject and allow the foam element to cure can be as much as several minutes. In addition, the type of material utilized to form the foam element can also be costly.
As it is known in the art, it is desirable to minimize manufacturing time and costs. Thus, there exists a need for an improved armrest and process of forming an armrest that reduces manufacturing and assembly time and costs, as well as material costs.